Question

So, here’s the situation: a rails app with two idioms, one where users use the format 5,000.40 for writing numbers (standard english), and the other 5.000,40.

Now the question is, how do I deal with this? I’m using the i18n helpers for dealing with output, but I don’t know how to process these numbers in my rails controller.

Answer 1

This is what I did to get this working:

Inside an initializer:

class ActiveRecord::Base

  class << self

    def handle_internationalization_numbers_for(*fields)
      fields.each do |field_name|
        define_method "#{field_name}=" do |other|
          if valid_number?(other)
            write_attribute(field_name, other)
          else
            # try converting it to a proper number
            write_attribute(field_name, other.tr(".,", ",."))
          end
        end
      end
    end

  end

  private

  def valid_number?(number)
    number.to_s.match(/\A[+-]?\d+?(\.\d+)?\Z/) == nil ? false : true
  end    

end

Then in your models:

handle_internationalization_numbers_for :field_1, :field_2